JPH04236111A - Device for monitoring accretion of snow on aerial power line - Google Patents

Abstract

PURPOSE:To easily recognize the adhesion of snow on an aerial wire from the rotated angle of the aerial wire. CONSTITUTION:A wire rotation measuring instrument 4 is integrally fitted to an aerial power transmission line 1A so that the instrument 4 can rotate together with the line 1A when the line 1A rotates due to adhered snow. The instrument 4 incorporates an annular passage surrounding the line 1A and a ball which rolls as the device 4 rotates is provided in the passage. The position of the ball does not rely on the rotation of the device 4, but always stays at the lowest position due to the gravity. The snow adhering state of the line 1A can be monitored by detecting the rotation of the aerial power transmission line 1A from the relative position between the passage and ball and sending the detected rotation to a remote supervisory device through an optical fiber 61.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a snow accumulation monitoring device for overhead power lines, and more particularly to a snow accumulation monitoring device that has a simple structure and can accurately monitor snow accumulation conditions.

0002

[Background Art] Today, power transmission lines are indispensable equipment in power supply operations, and accidents or failures of this equipment have a very serious impact on today's highly electrified society, and in some cases, power transmission lines are essential equipment for power supply operations. Social functions may be paralyzed. Therefore, an accident on a power transmission line is
In the electricity supply business, this must be avoided as a top priority.

[0003] One of the causes of accidents on power transmission lines is major accidents such as wire breakage due to snow deposits on wires, collapse of steel towers that support wires, or abnormal vibrations of snow-covered wires due to wind pressure. There are electrical accidents such as ground faults and short circuits in power transmission lines. In such situations, if snow accumulation on power lines can be monitored, accidents can be prevented or minimized by appropriate power supply operations or artificial snow removal before an electrical accident occurs, as described above. It is possible.

Therefore, in order to understand the snow accretion situation, a wire tension meter with a load cell inserted into the ground side of the insulator of the power transmission line is installed to measure the increase in load on the electric wire, and based on this measurement value, the snow accretion on the electric wire is determined. It has traditionally been done to understand the situation.

[0005]

However, the load on the electric wire varies greatly not only due to snow accumulation, but also due to changes in the temperature of the electric wire or wind even in the absence of snow. Therefore, even if the electric wire load fluctuates, it may not be possible to accurately determine the state of snow accumulation.

In addition, since the electric wire tension signal, which is a minute signal, is measured on a power transmission line under a high electromagnetic field, noise etc. become large and the necessary measurement accuracy cannot be obtained. In some cases, it was not possible to fully understand the situation.

Furthermore, the load cell itself inserted into the insulator is required to have extremely high mechanical strength and reliability, resulting in high cost.Moreover, it is difficult to insert a load cell having a certain length into the ground side insulator. This increases the length of the electric wire between the towers, which requires extra work to shorten the wire length, and further increases the installation cost.

[0008] Furthermore, the mechanical strength of the overhead power transmission line body may be impaired due to the insertion of the load cell.

[0009] An object of the present invention is to provide an overhead electric wire that can accurately grasp snow accretion conditions with a relatively simple structure without impairing the mechanical strength of the electric wire or increasing costs. The purpose of the present invention is to provide a snow accumulation monitoring device.

0010

SUMMARY OF THE INVENTION The present invention focuses on the fact that as snow accumulates on an overhead wire, the wire itself rotates. In the present invention, the term "overhead electric wire" refers not only to the main overhead power transmission line but also to the overhead ground wire.

[0011] In order to solve the above problems, the present invention has the following features:
A wire rotation measuring device that rotates with the rotation of the wire and measures its own rotation is attached to the overhead wire between the towers that support the overhead wire, and the output of this device is received to measure the rotation of the overhead wire. By measuring this, the state of snow accretion on the electric wires can be monitored.

[0012] This electric wire rotation measuring device can be configured such that a ball is movably disposed within an annular passage, the position of the ball within the passage is measured, and the measurement results are transmitted.

[0013] Furthermore, it is preferable that the wire rotation measuring device obtains a power source for driving the device from a current flowing through an overhead wire to which the device is attached.

[0014]

[Operation] According to the present invention, since the snow accumulation monitoring device is configured as described above, the overhead electric wire itself gradually rotates due to its gravity according to the amount of snow that has accumulated on the overhead electric wire, thereby causing the electric wire attached to the transmission line to rotate. The rotation measuring device will also rotate together. This rotation angle or amount of rotation is proportional to the amount of snowfall. The amount of rotation is measured electrically or optically, and the measured value is transmitted wirelessly or the like to a remote monitoring means. The monitoring means that receives this measurement value monitors the state of snow accretion on the electric wire based on the amount of rotation of the electric wire.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a configuration diagram showing the installation state of an overhead power transmission line to which a snow accumulation monitoring device according to the present embodiment is attached, and FIG. 2 is a plan view and diagram of an example of a wire rotation measuring device which is a main part of the snow accumulation monitoring device. 3 is a side view of an example of an electric wire rotation measuring device, FIG. 4 is an internal configuration diagram of an example of an electric wire rotation measuring device, FIG. 5 is a sectional view taken along the line A-A in FIG. 4, and FIG. FIG. 7 is a perspective view and a schematic circuit diagram of an example of a wire rotation measuring device.

As shown in FIG. 1, a plurality of steel towers for supporting overhead power transmission lines are provided at predetermined intervals. In the illustrated example, only two steel towers 31 and 32 are shown to simplify the explanation. A plurality of overhead power transmission lines 1 are suspended between these towers via insulators 20.
A to 1C are provided in an extended manner. Also, steel tower 31
, 32, an overhead ground wire 2 is similarly stretched across the upper ends of the wires.

The snow accumulation monitoring device according to the present invention is installed on the power transmission line constructed as described above. Specifically, this snow accumulation monitoring device includes a wire rotation measuring device 4 constituting a main part, and this measuring device 4 is connected to the power transmission lines 1A to 1A.
For example, it is attached in the middle between the towers of the top power transmission line 1A (upper phase electric line) of 1C. A monitoring means 21 is attached to one of the steel towers 32 to monitor the state of snow accumulation in response to measurement values transmitted from the measuring device 4.

As shown in FIGS. 2 to 6, the measuring device 4 is entirely covered by a donut-shaped, ie, annular case 49 with a through hole in the center. A gripping portion 41 is formed in which a plurality of, for example four, convex portions protrude inward in the radial direction in order to grip the power transmission line. And this case 49 is
In order to facilitate attachment to existing power transmission lines, it has a two-part structure divided into upper and lower halves, and by tightening the flanges 48, 48 provided at the respective joints with bolts 50, 50, The grip portion 41 firmly grips the power transmission line 1A so that the measuring device 4 can be attached to the power transmission line.

[0020] Inside the case 49, a passage 43 is provided which is formed into an annular shape by, for example, a plastic tube that can be divided into two parts, upper and lower, so as to surround the gripped power transmission line. A ball 42 made of, for example, a magnetic material is housed inside so as to be able to roll or move freely along the circumferential direction. The passage 43 is not limited to a pipe, for example, the case 4
The passage may be formed by making the wall 9 thicker and forming an annular groove therein. A plurality of metal detectors 44A to 44D, for example, four metal detectors 44A to 44D, are attached to the outside of the passage 43 at predetermined intervals along the circumferential direction, and the metal detectors 44A to 44D are installed at intervals of 90 degrees. It is now possible to detect the approach of

Further, inside the case 49, as shown in FIGS. 4 and 7, there is a determination circuit 4 connected to the detector 44 (44A~) for determining the measurement data therein.
5, a wireless transmission circuit 46 connected to this determination circuit 45 and for wirelessly transmitting measured data, and a wireless transmission circuit 46 for driving each of the detectors 44, determination circuit 45, and wireless transmission circuit 46. A power supply circuit 47 for supplying power to
is accommodated. This power supply circuit 46 is configured to obtain energy by electromagnetic induction from a load current flowing through a power transmission line to which this device is attached.

On the other hand, as shown in FIG. 1, the monitoring means 21 for receiving transmission data from the wireless transmission circuit 46 is attached to the top of the steel tower 32 closest to the measuring device 4 in order to directly receive the transmission data of weak energy. It has a receiving circuit 7. A processing circuit 8 is connected to the receiving circuit 7, and the data is processed as appropriate. A remote monitoring device 9 installed at a remote location, such as a maintenance office, is connected to this processing circuit 8 via a long cable, such as an optical fiber 61 that is not affected by electromagnetic induction. , where you can monitor snowfall conditions.

Next, the operation of the snow accumulation monitoring device configured as described above will be explained.

First, when snow begins to accumulate on each of the power transmission lines 1A to 1C, each power transmission line gradually rotates due to the weight of the snow. According to this rotation, the wire rotation measuring device 4 itself attached to the power transmission line 1A also rotates along with the power transmission line. At this time, even if the measuring device 4 rotates in its circumferential direction, the ball 42 provided movably within the passage 43 of the measuring device 4
Since it rolls due to its own weight, it stays at a fixed position, that is, at the lowest end of the passage 43.

On the other hand, since the metal detectors 44A to 44D provided outside the passage 43 rotate together with the case 49, when the power transmission line 1A rotates, for example, as indicated by arrow B in FIG. The device 4 also rotates in the same direction and by the same angle, and as a result, the metal detector 44A initially
had detected the presence of the magnetic ball 42, but as the sensor rotates, the detection intensity by the detector 44A gradually attenuates, and the metal detector 44B begins to detect the presence of the ball 42 instead. Now, assuming that the power transmission line 1A has rotated 90 degrees, and assuming that four metal detectors are installed as shown in the example, the detector 44A was initially detecting the maximum value; The detection value will gradually attenuate and instead detector 44B will detect its maximum detection value.

The measured values detected by each of the metal detectors 44A to 44D are transmitted to the receiving circuit 7 of the monitoring means 21 via the determination circuit 45 and the wireless transmission circuit 46. At this time, since the power supply circuit 47 obtains energy from the load current of the power transmission line 1A as the driving power for the measuring device 4, a separate power source such as a battery is not required.

The measurement data received by the receiving circuit 7 is as follows:
The signal is transmitted to the remote monitoring device 9 via the processing circuit 8 and the optical cable 61. The monitor operating this monitoring device 9 can recognize in which direction and by how much angle the power transmission line 1A has rotated, for example, by 90 degrees in the direction of arrow B. Since this rotation angle naturally has a correlation with the amount of snow accretion on the power transmission line, the observer can accurately recognize the snow accretion situation. In this case, the correlation between the detection strength of each detector and the rotation angle of the power transmission line is stored in advance in, for example, a computer in the remote monitoring device 9, and the rotation angle and the snowfall amount are determined based on the measurement data. may be obtained by calculation. For example, metal detector 44A
If the detected values of the metal detector 44B and the metal detector 44B have the same intensity, the magnetic ball 42 will be located exactly between these detectors 44A and 44B, and the observer will be able to see that the power transmission line is at a 45 degree angle in the direction of the arrow B. It is possible to recognize that the vehicle has rotated, and take measures against snow accumulation based on this value.

As described above, according to this embodiment, the snow accretion situation can be ascertained by determining the amount of rotation of the power transmission line using a wire rotation measurement device installed on the power transmission line. This eliminates fluctuations and allows for an accurate understanding of snowfall conditions.

[0029] Furthermore, since there is no element affected by the high electromagnetic field from the power transmission line, there is no room for noise etc. to enter, so it is possible to improve measurement accuracy and furthermore, it is possible to accurately grasp the snow accretion situation. can.

[0030] Since the load cell used in the conventional technology can be made unnecessary, the work of shortening the wire length due to the insertion of the load cell can be eliminated, and not only can construction costs be significantly reduced, but also mechanical A decrease in strength can be prevented.

Although four metal detectors are provided in the above embodiment, the number is not limited to this number, and the number may be further increased if, for example, it is desired to further improve the detection accuracy. Of course.

Furthermore, in the above explanation, the rotation of the power transmission line is measured by a combination of a metal detector and a magnetic sphere, but this is not limited to this, and an optical method may be used, for example, by using a mirrored sphere as a magnetic sphere, and By providing a spherical detector consisting of a light-emitting element and a light-receiving element instead of a metal detector, the emitted beam from the light-emitting element of the spherical detector hits the mirrored sphere and is reflected, and the reflected light is detected by the light-receiving element. It may also be configured to measure rotation.

Furthermore, the wire rotation measuring device may be connected to a strong rod-shaped member, or one end of the wire rotation measuring device may be
It may be suspended and fixed from the power transmission line so that it exerts an effect similar to a weight that suppresses the rotation of the power transmission line. According to this, the power transmission line becomes difficult to rotate, and as a result, it is possible to suppress the growth of snow accumulation.

[0034]

[Effects of the Invention] According to the present invention, since the amount of snow accumulation is determined from the rotation of overhead electric wires caused by snow accumulation, the mechanical strength of the electric wires is not impaired, and furthermore, the cost does not increase. , it is possible to accurately grasp snowfall conditions with a relatively simple configuration. Furthermore, when power for the device is obtained from the electric wire to which the device is attached, maintainability is improved.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the installation status of an overhead power transmission line to which a snow monitoring device according to the present invention is attached.

FIG. 2 is a plan view showing a wire rotation measuring device.

FIG. 3 is a side view of the wire rotation measuring device.

FIG. 4 is an internal configuration diagram showing a wire rotation measuring device included in the snow accumulation monitoring device according to the present invention.

FIG. 5 is a sectional view taken along line A-A in FIG. 4;

FIG. 6 is a schematic perspective view of the electric wire rotation measuring device divided in half.

FIG. 7 is a schematic circuit diagram of a wire rotation measuring device.

[Explanation of symbols]

1A power transmission line 1B Power transmission line 1C power transmission line 4 Wire rotation measuring device 7 Receiving circuit 8 Processing circuit 9. Distant monitoring device 21 Monitoring means 31 Steel tower 32 Steel tower 41 Gripping part 42 Ball 43 Passage 44A Metal detector 44B Metal detector 44C metal detector 44D metal detector 49 case 61 Optical fiber

Claims (3)

[Claims] Claim 1: An electric wire rotation measuring device that rotates with the rotation of the electric wire and measures its own rotation is attached to the overhead electric wire between the steel towers that support the overhead electric wire, and the output of this device is received. 1. A snow accretion monitoring device for overhead power lines, characterized in that the state of snow accretion on overhead power lines is monitored by measuring the rotation of the electric wires. 2. The electric wire rotation measuring device is characterized in that a ball is movably arranged in an annular passage, the position of the ball in the passage is measured, and the measurement result is transmitted. The snow accumulation monitoring device for overhead electric wires according to claim 1. 3. The electric wire rotation measuring device according to claim 1, wherein a power source for driving the device is obtained from a current flowing through the electric wire to which the device is attached. Snow accumulation monitoring device for overhead power lines.